Organic compositions containing a metallo cyclopentadienyl



c'omposition containinga metallo cyclopentadienyl. metallo cyclopentadienyl is a metal derivative ofa cyclope'ntadiene, i.e., a 'compound-Whi-ch'c'ontains a cyclo'pentadiene ring. Examples 'of the cyclopentadienes from, which' wecanprepare themetallo cyclopentadienyls are ORGANIC COMPOSITIONS CONTAINING A- NIETALLO CYCLOPENTADIENYL DonaldR. Stevens, Wilkinsburg, and Ronald L. Sweet,

Baldwin Township, Allegheny County, Pa., assignors to :Gulf Research & Development Company, Pittsburgh,

Pa.,' acorporation'of Delaware NoDrawing, Filed Apr. 21, 1952, Ser. N0.'283,513

7 Claims. (Cl.-25249.7)

This invention relates to organic compositions containingadvant'ageous addition -agents and particularly to hydrocarbon compositionscomprising gasoline anda novel anti knock agent.

The compositions of the invention comprise an organic A illustratedby' the following structural formulas:

HAR

Wherein 'R is a substituent selected'from the group consisting of hydrogen, alkyl, alkene, cycloalkyl, and aryl .pentadiene; ethylcyclopentadienes; methyl, ethylcyclopentadienes; n-propylcyclopentadienes; isopropylcyclopentadienes; propenylcyclopentadienes; "methyl, propylcyclopenta'dien'es; n-butylcyclopentadienes; sec-bu'tylcyclo'pen- 'ta'dienes; tert-btitylcyblopentadienes; isobutylcyclopenta- 'dienes; 'amylcyclopentadienes; cyclopentylcyclopentadienes; cycloheXylcyclopentadienes; phenylcyclopentadienes;" diphen'ylcy-clopentadienes; pentaphenylcyclopentadiene; iridenegfluorene; and the like,

The'metallo "derivatives of the cyclopentadienes,some

ofwhich are believed to "be new compounds, can be employed in accordance with the invention as' addition agents to"various organic compositions, particularly hydrocarbons comprising 'gasolines and other petroleum products such as lubricating oils, turbine oils, transformer oils, kerosenes, diesel fuels, jet fuels, fuel oils, greases, asphalts,

waxes, insecticides, and the like. "Examples of the metallo derivatives ofthe cyclopenta'dienes employed in the compositions 'of' the'pres'e'nt invention are illustrated "by the following structural formulas:

wherein R is a substituent selected from the group consisting of hydrogen, alkyl, alkene, cycloalkyl, and aryl "radicals; M is ametaL parti-cuIarIyiron, copper zinc,

tin, lead, aluminum, magnesium, potassium, sodium, bismuth, tellurium, selenium, nickel,- c obalt, cadmium, and antimony; and x' is the=valence of the-metal.

Our invention is particularly important with respect to increasing the octane number of gasolines.

dicyclopentadienyl to a gasoline greatly improves its anti- United States Patent For instance, -we have found that the addition of asmall amount of iron fluxed for several hours.

3,294,685 Patented Dec. 27, 1966 ice about 0.05 and 5.0 grams'perthousand milliliters, i.e.

between about 0.2 and 20 grams of metallo cyclopentadienyl per gallon of gasoline. Wehave'found that 0.5

"gram of 'irondicyclopentadienyl per thousand milliliters of gasoline 'gives anincrease in octane number corresponding substantially tothe increase obtained by the additionof one cubic centimeter of'lead tetraethyl per gallon of gasoline. 'One cubic centimeter of lead tetraethyliper' gallon of gasoline is equivalent to about 0.45 gram of lead tetraethyl per thousand milliliters of gasoline.

The metallo cy-clopentadienyls employed in the present invention-can be prepared in various ways. For example, iron dicyclopentadienyl can be prepared by passing a'mix- 'ture of'cyclopentadiene and nitrogen over a reduced iron 1 catalyst at 300-C. Thismethod, however, requires frequent reactivation of the catalyst.

It has been disclosed by S. A. Miller, J.'A.Tebboth and] Tremaine, Journal of The Chemical Society, 632, February 1952. Another method of preparing iron dicyclopentadienyl comprises a Grignard synthesis starting with cyclopentadiene, ethyl magnesium bromide and ferric chloride. This method for the preparation of iron dicyclopentadienyl has been disclosed by T. J Kealy and P. L. 'Pauson in Nature, 168, 1039 (1951).

The iron dicyclopentadienyl employed in the compositions hereinafterset forth was prepared by the latter method. Specifically, the Grignard reagent was prepared by reacting 16.0 grams of magnesium with 73.0 grams of ethyl bromide in dry ether. To the reaction: mass thus formed :was added 44.0 grams of cyclopentadiene with rapid stirring over a period of five minutes while maintaining a; gentle reflux. The reaction occurring is illustrated as follows:

. anhydrousferric chloride in the form of an ethereal-solution. The perric chloride ethereal solution was added dropwise'wi'th stirring and the reaction mixture waste- The reactions occurring during this period are illustrated as follows:

Unreacted' Grignard reagent was decomposed by treating thereaction mass with ammonium chloride. The iron dicyclopentadienyl was then recovered by extraction with benzene. "The benzene was removed by distillation leavcyclopentadienyl on the octane number of gasoline, a straight-run Mid-Continent gasoline having an ASTM octane number (Motor Method) of 60.5 was employed. When iron dicyclopentadienyl was added to this gasoline in an amount corresponding to 0.1 gram per liter, the octane number was increased to 64.7. When the amount of iron dicyclopentadienyl added was 0.3 and 0.5 gram per liter, the octane number was increased to 68.2 and 70.4, respectively. The octane number was further increased to 73.2 when iron dicyclopentadienyl was used in an amount corresponding to 1.0 gram per liter of gasoline. When 0.45 gram of lead tetraethyl was added to a liter (1 cc./ gal.) of the straight-run gasoline, the octane number was increased to 71.4. It can thus be seen that iron dicyclopentadienyl is about as effective in increasing the octane number. of gasoline as lead tetraethyl. It should be understood, of course, that various scavenging agents such as the halides of ethylene can be added to the gasoline to assist in removing iron as volatile halides from the engine during combustion. For example, we may employ a mixture of ethylene dibromide and ethylene dichloride in conjunction with a metallo cyclopentadienyl in gasoline.

It should be further understood that the gasoline may contain other additives including dyes, antioxidants, antirust agents, antistalling agents, and the like. In some instances the compounds of the type disclosed herein may be used in conjunction with other anti-knock agents.

Compounds of the type disclosed here in are also useful in oils, waxes, wax distillates, and asphalts when accelerated oxidation of these compositions is desired. The mechanism of the pro-oxidizing effect of the metallo cyclopentadienyls has not been definitely established. In order to illustrate the increased amount of oxidation that can be obtained when a small amount of iron dicyclopentadienyl is added to an oil, an oxidation test was carried out in a reaction chamber thermostatically con trolled to maintain the temperature at about 170 C. The test comprises circulating pure oxygen through a sample of the heated oil. The amount of the oxygen circulated is maintained constant by replacing the oxygen consumed. The oxygen which is circulated, on leaving the hot reaction chamber, passes through a separation train to remove volatile acids, water, and carbon dioxide. The oxygen is then returned to the reaction chamber.

When the above test had been carried out for -12 hours and 45 minutes on a mineral oil of paraflinic type having a molecular weight of about 350 to 450, 35 units of oxygen I were taken up by the oil. When another sample of the oil containing 0.019 gram (0.05 percent) of iron dicyclopentadienyl was subjected to the same test, the same amount of oxygen (35 units) was taken up in 43 minutes. The induction period for the oil alone was 4 hours and 45 minutes. The oil containing the iron dicyclopentadienyl had an induction period of only minutes. The pro-oxidizing effect of iron dicyclopentadienyl on oils is thus readily apparent.

We have found that fuels comprising hydrocarbons containing between about 0.1 and 1.0 percent by weight of iron dicyclopentadienyl burn with a much cleaner flame than the same fuels containing no iron dicyclopentadienyl. Fuels which burn with less smoke are particularly desirable when they are used in automobile engines, diesel engines, jet engines, lamps, oil burners, and the like.

Wax candles containing between about 0.1 and 1.0 percent by weight of iron dicyclopentadienyl have been found to burn with a higher, brighter flame than similar candles containing no iron dicyclopentadienyl.

'Dhe insecticidal properties of naphtha compositions containing iron dicyclopentadienyl have been determined in a Barnhart Settling-Mist Tower. This apparatus is described in an article entitled Tests on Crawling Insects by F. L. Campbell, C. S. Barnhart, and J. M. Hu-tzel, Soap and Sanitary Chemicals, pages 105 et seq.,

July 1941. A test spray was prepared by dissolving 2.5 grams (3.2 percent) of iron dicyclopentadienyl in ml. of a typical household insecticide base oil. The tests made with this solution employed a dosage of IO-second discharge. An equilibrium :period of 15 seconds followed by an exposure period of 70 seconds, during which the mist was permitted to settle on adult house flies confined in a screen-covered dish, was employed in the tests. The results of the tests showed that of the flies which had been contacted with the base oil containing 3.2 percent by weight of iron dicyclopentadienyl, 53.6 percent were dead after 24 hours. Of theflies which were contacted with the base oil alone, only 13.0 percent were dead after 24 hours. Check flies which were confined for 24 hours without having been contacted with either the base oil or the base oil containing iron dicyclopentadienyl had a death rate of only 0.4 percent. The better than fifty percent mortality of the flies treated with the base oil containing iron dicyclopentadienyl is indicative of the insecticidal properties of naphthas containing a small amount of iron dicyclopentadienyl. Naturally, the amount of metallo cyclopentadienyl used in insecticidal compositions-will vary with the particular compound employed and also depends upon the particular insects for which the spray is intended. The amount of iron dicyclopentadienyl employed in insecticidal compositions intended for use on flies is between about 1.0 and 10.0 percent by weight.

While our invention has been described above with reference to various specific examples and embodiments, it will be understood that the invention is not limited to such illustrated examples and embodiments and may be variously practiced within the scope of the claims hereinafter made.

We claim:

1. A bis-(lower alkyl substituted cyclopentadienyl) iron compound having the formula:

in which C H is the lcyclopentadienyl radical and R is a lower alkyl radical.

2. A composition of matter comprising an organic composition selected from the group of hydrocarbons consisting of lubricating oils, turbine oils, transformer oils, fuel oils, greases, asphalts, waxes, wax distillates and insecticidal naphthas and a minor amount, relative to said hydrocarbon, of a dicyclopentadienyl iron.

3. A normally liquid hydrocarbon fuel oil containing dicyclopentadienyl iron in an amount suflicient to render said fuel oil clean burning.

4. A composition of matter consisting essentially of candle wax and a minor proportion of iron dicyclopentadienyl suflicient to improve the burning characteristics of said candle wax.

5. A liquid hydrocarbon fuel containing a lower alkyl dicyclopentadienyl iron in an amount suflicient to increase the anti-knock characteristics of said fuel.

6. A composition consisting of a major proportion of a fuel oil normally tending to smoke when burned and a minor proportion suificient to substantially reduce such smoking, of iron dicyclopentadienyl.

7. An improved fuel consisting of a fuel oil containing between about 0.1 and about 1.0 percent by weight if iron di-cyclopetadienyl.

References Cited by the Examiner UNITED STATES PATENTS 2,134,625 10/1938 Shappirio 4469 X DANIEL E. WYMAN, Primary Examiner.

JULIUS GREENWALD, WILLIAM G. WILES, ABRA- HAM H. WINKELSTEIN, Examiners.

F. CROWLEY, L. R. ROSDOL, J. C. LANGSTON,

Y. H- SMITH, Assislant Examiners. 

2. A COMPOSITION OF MATTER COMPRISING AN ORGANIC COMPOSITION SELECTED FROM THE GROUP OF HYDROCARBONS CONSISTING OF LUBRICATING OILS, TURBINE OILS, TRANSFORMER OILS, FUEL OILS, GREASES, ASPHALTS, WAXES, WAX DISTILLATES AND INSECTICIDAL NAPHTHAS AND A MINOR AMOUNT RELATIVE TO SAID HYDROCARBON, OF A DICYCLOPENADIENYL IRON. 